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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 11 |
| 7 | 96 |
| 8 | 756 |
| 9 | 5616 |
| 10 | 40176 |
| 11 | 279931 |
| 12 | 1912811 |
| 13 | 12876066 |
| 14 | 85650696 |
| 15 | 564264576 |
| 16 | 3687717456 |
| 17 | 23938890361 |
| 18 | 154507689791 |
| 19 | 992285228496 |
| 20 | 6345103937976 |
| 21 | 40418727227856 |
| 22 | 256599474317136 |
| 23 | 1624110448674691 |
| 24 | 10251689936941271 |
| 25 | 64551976895557626 |
| 26 | 405560928053970756 |
[0,0,0,0,0,1,11,96,756,5616,40176,279931,1912811, 12876066,85650696,564264576,3687717456, 23938890361,154507689791,992285228496, 6345103937976,40418727227856,256599474317136, 1624110448674691,10251689936941271, 64551976895557626,405560928053970756] |